The cleansing of skin with surface-active cleansing preparations has become a focus of great interest. Many people wash and scrub their skin with various surface-active preparation several times a day. Ideal skin cleansers should cleanse the skin gently, causing little or no irritation, without defatting and overdrying the skin r leaving it taut and rough after frequent routine use. Most lathering soaps and synthetics, liquids and bars included, fail in this respect.
Soaps have for many years been employed as cleansing agents for the skin. Soaps are not mild to the skin, thus the incorporation of additives to improve the performance of soap is a common practice. Superfatting agents, such as lanolin, fatty acid derivatives and lecithin, are often added to mitigate the degreasing effect of the soap on skin. The ability of superfatting agents to produce a soft skin feel is of limited duration.
Certain synthetic surfactants are known to be particularly mild. However, a major drawback of most mild synthetic surfactant systems when formulated for skin cleansing is poor lather performance, when compared to the highest bar soap standards (bars which are rich in coconut soap and superfatted). On the other side, the use of known high sudsing anionic surfactants with lather boosters can yield acceptable lather volume. Unfortunately, the highest sudsing anionic surfactants are, in fact, poor in clinical skin mildness. Surfactants that are among the mildest, such as alkyl (sodium lauryl) glyceryl ether sulfonate (AGS), are marginal in lather. It will be appreciated that these two factors, lather and skin mildness, make the surfactant selection a delicate balancing act.
It is known that moisturizers can provide skin conditioning benefits in cleansing products. For example, glycerin and/or free fatty acids are added to bars or liquid cleansing products for skin benefits. Likewise, certain polymeric skin feel aids can also provide unique tactile characteristics to both the lather and the skin during rinsing. Unfortunately, conventional moisturizers/emollients and polymeric skin feel aids provide a softening effect on human skin while leaving the skin feeling greasy, sticky or tacky.
Silicones have been disclosed for several used in toilet bars. It has been disclosed in Czechoslovakian Patent 195511, List et al., issued May 15, 1982, to incorporate dimethylsiloxane into toilet and shaving soaps to prevent bloom, to decrease bar drying and cracking, and to increase soap homogeneity and plasticity. U.K. Patent Application 2,041,964, Cooper, published Sep. 17, 1980, has disclosed the use of silicone compounds as fragrance-imparting components in bar soaps. Polysiloxane fluids have been taught in East German Patent Application 76293, Limbach et al., published Sep. 20, 1970, to provide a protective film to the skin, to better fixate the perfume and to prevent surface softening of soap bars after contact with water. U.S. Pat. No. 4,279,765, Hill et al., issued Jul. 21, 1981, has disclosed the use of amine-substituted polydiorganosiloxanes to impart a durable soft, silky feel to the skin contacted with the soap bar.
It has now been discovered that mild skin cleansing toilet bar compositions which comprise from about 0.5% to about 20% of a silicone component, consisting of a mixture of silicone gum and silicone fluid, provide durable skin conditioning, superior smooth and soft skin feel, lather and improved rinsing. The use of toilet bar compositions which contain a silicone gum and fluid blend component provides superior skin conditioning without negative tactile attributes such as greasy, sticky or tacky skin feel. Unexpectedly, toilet bar compositions with a silicone gum and fluid blend component provide reduced skin tautness after washing. The skin feel and conditioning imparted by the silicone gum and fluid blend is superior to that provided by the use of silicone fluid alone. In addition, the silicone gum/fluid blends are easier to process in the mild skin cleansing toilet bars of the present invention than the silicone gum alone. Surprisingly, since silicones are known as suds/lather reducers, the silicone gum/fluid blends do not suppress lather in the present invention, even when mild surfactants, which are not known for robust lather, are included.
Silicone gum and fluid blends have been disclosed for use in shampoos and/or conditioners in U.S. Pat. No. 4,906,459, Cobb et al., issued Mar. 6, 1990; U.S. Pat. No. 4,788,006, Bolich, Jr. et al., issued Nov. 29, 1988; U.S. Pat. No. 4,741,855, Grote et al., issued May 3, 1988; U.S. Pat. No. 4,728,457, Fieler et al., issued Mar. 1, 1988; U.S. Pat. No. 4,704,272, Oh et al., issued Nov. 3, 1987; and U.S. Pat. No. 2,826,551, Geen, issued Mar. 11, 1958, all of said patents being incorporated herein by reference. The art does not suggest the use of a silicone gum and fluid blend in a mild skin cleansing toilet bar nor does it suggest that use of such a blend in a mild skin cleansing toilet bar would provide any skin conditioning and moisturizing properties, let alone the superior durable skin conditioning and moisturizing as defined herein, without greasy, sticky, tacky or taut skin feel negatives.
The present invention encompasses a mild skin cleansing toilet bar comprising a specifically defined silicone component which provides improved skin feel, skin conditioning, rinsing and ultra skin mildness without negative tactile attributes, such as greasy, sticky, tacky or taut skin feel.